Catheter delivery device

ABSTRACT

In a device for ejecting a catheter into a passageway like a blood vessel, the device including a housing containing a catheter extending or extendable into a feeding nose, such as a cannulated needle, the housing interior to be fluid pressurized to effect fluid flow around the catheter. The catheter is inwardly compressible and of a size where the outer diameter is about equal to and preferably somewhat greater than the inner diameter of the needle lumen. The build-up of fluid pressure within the housing of the device was found to compress the catheter making it of a smaller diameter than the needle lumen and in the process forming, at least during the initial stages of catheter movement, a catheter with a piston-like profile so that the catheter is impelled by fluid friction and piston action.

United States Patent [191 Smith [111 3,826,256 51 July 30, 1974 1 1CATHETER DELIVERY DEVICE [75] Inventor: Gordon E. Smith, Sun Prairie,Wis.

[73] Assignee: Medidyne Corporation, Chicago, 111.

[22] Filed: Jan. 13, 1972 [21] Appl. No.: 217,468

[52] US. Cl 128/2144, 128/348, 221/64, 221/278, 226/97 [51] Int. Cl A6lm5/18 [58] Field of Search 128/2144, 221, 218 R,

[56] References Cited UNITED STATES PATENTS 2,518,165 8/1950 Millard128/2l4.4 2,999,499 9/1961 Willet 128/214.4 3,010,453 11/1961 Dohcrtyml128/214.4 3,185,152 5/1965 Ring 128/221 X 3,262,449 7/1966 Pannier, Jr.et a1. 128/2144 3,463,152 8/1969 Sorcnson 128/2144 3.509.880 5/1970Guttman 128/221 3,561,445 2/1971 Katerndahl et a1. 128/2144 3.572.3343/1971 Pctterson 128/214.4 3,633,579 1/1972 Alley 3.703.174 11/1972Smith 128/348 X FOREIGN PATENTS OR APPL1CAT1ONS Germany 128/2144 PrimaryExaminerRichard A. Gaudet Assistant Examiner-J. C. McGowan Attorney,Agent, or Firm-Wallensteen, Spangenberg, Hattis & Strampel [57] ABSTRACTIn a device for ejecting a catheter into a passageway like a bloodvessel, the device including a housing containing a catheter extendingor extendable into a feeding nose, such as a cannulated needle, thehousing interior to be fluid pressurized to effect fluid flow around thecatheter. The catheter is inwardly compressible and of a size where theouter diameter is about equal to and preferably somewhat greater thanthe inner diameter of the needle lumen. The build-up of fluid pressurewithin the housing of the device was found to compress the cathetermaking it of a smaller diameter than the needle lumen and in the processforming, at least during the initial stages of catheter movement, 'acatheter with a piston-like profile so that the catheter is impelled byfluid friction and piston acmen.

27 Claims, 24 Drawing Figures PAIENIEB mums snmsor 7.

CATHETER DELIVERY DEVICE This invention relates to a catheter deliverydevice which incorporates the invention of and is an improvement overthe catheter delivery devices disclosed in my application Ser. No.54,732 entitled METHOD AND APPARATUS FOR CATHETER INJECTION filed July14, 1970. The catheter injection devices disclosed in this applicationand the catheter device which is the subject of the present inventionutilize the build-up of fluid pressure in a catheter housing having afeeding nose for guiding the catheter, to cause the flow of fluidbetween the catheter and the inside wall of the feeding nose (which maybe a cannulated needle) to inject the catheter within a body passagewaysuch as a blood vessel. Where the catheter is to be injected into ablood vessel, the catheter material is most advantageously very limp tominimize irritation of the blood vessel walls and to enable the catheterreadily to follow irregular paths within the blood vessel.

It is desirable to make the outside diameter of the catheter as close aspossible to the outer diameter of the needle through which it passes, sothat upon removal of the needle after catheter injection, the skin,blood vessel wall and other tissue punctured by the needle will contractas tightly as possible around the catheter to minimize leakage of fluidaround the catheter. ldeally, therefore, although limitations on theoperation of catheter delivery devices heretofore was thought tomitigate against the same, it would be desirable for the catheterdiameter to be equal to and even greater than the diameter of thedefining walls of the needle lumen'through which it is guided into ablood vessel or other passageway. However, despite the obviousdesirability for catheters of a diameter as close to the needle diameteras possible, prior to the present invention, catheters placed in bodypassageways, like blood vessels, using the lumen of a cannulated needleor other feeding nose as an exterior guiding means, were always of asize smaller than the lumen of the guiding means, so that the cathetercan freely slide or pass through the lumen. For example, if astiffcatheter of the same size as the lumen of the guiding means is utilized,the friction between the catheter and the lumen would be such that thecatheter could not be advanced through the lumen of the guiding means.Even in the case of limp flexible catheters like that used in thecatheter delivery devices disclosed in said copending application, wherethe catheter is ejected from the lumen of the guiding means by the flowof fluid around the catheter, it was thought necessary to utilize acatheter diameter smaller than the diameter of the lumen of the guidingmeans by a number of thousandths of inches to provide clearance for theready flow of fluid around the catheter so the fluid would not flowthrough the catheter and expand the same against the lumen of theguiding means, and to keep the manual compression forces necessary tobuild up a fluid eject a long catheter an appreciable length from thecatheter delivery device involved. in such case, the impelling force onthe catheter is the friction between the fast moving stream of liquidmoving around the catheter and the outside walls of the catheter. It wasfound that in mass producing the catheter delivery devices of certaincatheter sizes, a certain percentage of the catheters would not ejectfrom the devices.

In the present invention, for a given needle size, a larger catheter canbe ejected from the needle than was thought heretofore possible andgreater catheter ejection velocities are obtained for a modest increasein fluid pressure making catheter injection more effective, especiallyin circumstances when the catheter must be ejected substantial distancesthrough irregular paths within blood vessels and the like. Moreover, thepresent invention has substantially reduced the reject ratios to a pointwhere practically all manufactured catheter delivery devices areoperable in ejecting their catheters with appreciable velocities.

The present invention is based on my discovery that where an elasticcatheter which is compressible is utilized, most preferably one made ofa soft, very pliable rubber-like material having the limp resilient andinert quality of a silicone elastomer and the outer diameter of thecatheter is made at least about equal to at least the minimum diameterof the needle lumen (i.e. some needle lumens have a variation indiameter) and preferably at least equal to or, even better, slightlylarger than the diameter of the entire length of a needle lumen, whereit would be assumed that the fit between the catheter and defining wallsof the needle lumen would prevent any catheter ejection, the catheter isactually ejected at a higher velocity'and more readily for a modestincrease in manual force applied to a squeeze bulb or the like than inthe case where a small but finite clearance was provided as describedabove.

In examining into the possible reasons, it was concluded that the fluidpressure within the catheter delivery device housing was instrumental incompressing the catheter so that the catheter within the needle lumen isvery closely spaced from the walls of the needle lumen during theapplication of the fluid pressure. Also, for a given pressure, a greatervelocity of fluid flow results in the very small clearance between thecatheter and needle lumen walls which increases the fluid shear forcesacting on the catheter. The pressure acting on the catheter is believedto provide, during at least the initial catheter ejection operation, aforwardly and outwardly flaring profile which provides a rearwardlyfacing shoulder against which the force of fluid ejected from the needlelumen is applied to substantially increase the ejection force on thecatheter. Thus, there is both a piston-like action and an increasedfrictional force acting on the catheter aiding the cather ejectionprocess. It should be noted that where the catheter is the same size orlarger than substantially the entire length of the needle lumen whilethe increase of fluid pressure within the housing of the catheterdelivery device provides an external inward compressive force on theradially outwardly facing surfaces of the catheter located rearwardly ofthe needle lumen, one would think that the radially outwardly facingsurfaces of the portion of the catheter inside the needle lumen withwhich the catheter makes engagement are not so exposed and thus remainuncompressed where it cannot be moved from the needle. However, thejunction between the initially compressed and uncompressed portions ofthe catheter is not an abrupted right angled juncture, but is agradually forwardly and outwardly flaring portion which has bothradially outwardly and rearwardly facing components, so that there is asurface against which the pressure can act to compress the same radiallyinwardly. The aforementioned forwardly and outwardly flaring profile ofthe catheter, which initially is located at the point where the catheterfirst enters the needle lumen of the same or smaller size, under theapplication of fluid pressure is caused to progressively move down thelength of the catheter toward the front of the needle. Finally, theentire catheter leaves contact with the needle lumen at the end of theneedle lumen where the fluid pressure on the catheter is greatly reducedpermitting the catheter to expand at this point to its initial size. Thecatheter then has a piston-like profile at the end of the needle lumenand also, it is believed, an outwardly flaring profile within the needlelumen and so presents rearwardly facing surfaces against which themoving fluid applies a force to aid in catheter ejection. Thus, at theinstant when the catheter looses contact with the needle lumen walls,the catheter is free to be impelled by both the increased frictionalforces of the flow of fluid which then begins around the catheter andalso by the force of the fluid flow against the rearwardly facingcomponent of the catheter profile.

In the case where a needle hub is swaged upon the end of a cannulatedneedle body, there is generally produced an inwardly extending shoulderat the point where the swaging operation is carried out which is oflesser size than the rest of the needle lumen. A pistonlike actiondescribed above can be achieved by a catheter having a diameter which isequal to or somewhat larger than the diameter of the swaged portion ofthe needle lumen but of a smaller diameter than the rest of the lumen.In this case, upon application of fluid pres sure, a piston-like profileis formed just beyond the shoulder and since the catheter initiallyengages the lumen over only a very small length of the needle lumen, thecatheter instantaneously leaves contact with the needle lumen and apiston-like action immediately takes place to aid in moving the catheterboth by the friction of the moving fluid around the catheter and by theforce of fluid pressure against the rearwardly facing portion of thecatheter profile.

It should be noted that even if it were appreciated that the applicationof fluid pressure within the housing of the catheter delivery deviceprovides an external inward compressive force on the radially outwardlyfacing surfaces of the catheter initially engaging the needle lumenwalls, one would think also that there would be an equal radiallyoutwardly directed pressure on the inside of the catheter which wouldcancel out such compressive force. However, as soon as fluid starts toflow within the catheter, there is a pressure drop along the catheterinterior which, because the rear end of the catheter is usually asubstantial distance from the point where the catheter makes contactwith the needle lumen walls, results in a substantial pressure dropthereat. The substantial fluid pressures which are readily built upwithin a catheter delivery device by the squeezing of a bulb or the likewas found easily to overcome any opposition to compression of thecatheter even when the catheter is larger in size than the entire lengthof the needle lumen because of the pressure drop within the catheter.

There is, however, a problem with regard to flushing air out of acatheter delivery device of the invention where liquid is used to impelthe catheter into a blood vessel. In the most preferred form of thepresent invention, the catheter delivery device is manufactured in astate where it has to be subsequently filled with a sterile liquid likesaline solution or other liquid. When air is expelled by the charging ofthe catheter delivery device having a catheter of a smaller size thanthe needle lumen, by pointing the needle end thereof upwardly andfeeding liquid into the bottom portion of the device, as the liquidrises within the device it readily fills both the space around thecatheter and the catheter interior and drives the air ahead of the same.However, when the catheter is made of a size where it engages the wallsof the needle lumen, the small head pressures which are normally present(for example where an infusion liquid from a hanging infusion bottle iscaused to enter the catheter delivery device the head pressure isusually only about 2-3 feet of liquid) are insufficient to overcome theopposition to compression of the catheter for normal catheter lengths(e.g. 9 inches) and some air remains trapped within the device which isexpelled when the catheter is impelled by the liquid moving around thecatheter.

Another aspect of the present invention, therefore, is in overcomingthis in one of two ways. In one form of the invention, the catheterutilized is made of an unusually long length which length depends uponthe inside diameter of the catheter so that the pressure drop occurringwhen the liquid rises in the catheter is so substantial at the pointwhere the catheter contacts the needle lumen walls that even a few feetof head pressure is sufficient to compress the catheter to permit liquidand air to pass air around the catheter. In another form of theinvention, where the catheter is of a more common length, such as 9inches, a similar result is achieved by forming a partial obstruction atthe rear of the catheter which effects a substantial pressure drop orhinderance to liquid flow at this point, so that in effeet a similarpressure drop is present at the points where the catheter makes contactwith the needle lumen walls.

In accordance with another feature of the present invention, thecatheter injection device is provided with its own valve so that at anydesirable time the device can be charged with a sterile liquid anddisconnected from the source of liquid and be ready immediately to beused where the catheter injection operation is desired.

Another feature of the invention relates to an improved infusionliquid-receiving adapter assembly carried on the feeding nose of acatheter delivery device and which can easily be pulled from the feedingnose together with the rear end portion of an ejected cathetertemporarily held in the feeding nose lumen, and then sealingly relatedto the released end of the catheter.

The above and other features and advantages of the invention will becomeapparent uponn making reference to the specification to follow, theclaims and the drawings wherein:

FIG. 1 illustrates an initially liquid-free catheter delivery device inits packaged condition;

FIG. 2 is a longitudinal, sectional view through the catheter deliverydevice shown in FIG. 1, after it is removed from the package;

FIG. 3 is an enlarged, longitudinal, sectional view through the rear endportion of the catheter delivery device of FIG. 2, taken along sectionline 3-3 therein;

FIG. 4 is an enlarged, transverse, sectional view through the rear endportion of the catheter delivery device of FIG. 2, taken along sectionline 4-4 therein;

FIG. 5 is an enlarged, transverse, sectional view through the front endportion of the catheter delivery device shown in FIG. 2, taken alongsection line 5-5 thereof;

FIG. 6 is a view showing the catheter delivery device of FIGS. 1-5connected to an infusion bottle assembly for filling the delivery devicewith liquid and oriented to expunge air therefrom;

FIG. 7 is a transverse sectional view of that portion of the rear end ofthe catheter delivery device shown in FIG. 4 when the portion shown insqueezed to open the check valve formed thereby;

FIG. 8 is an enlarged, fragmentary, longitudinal, sectional view throughthe front end portion of the catheter delivery device of FIGS. l-4during the time air is being expunged therefrom;

FIG. 9A is a greatly enlarged, fragmentary, longitudinal sectional viewof the front and rear end portions of the catheter containing portionsof the catheter delivery device of FIGS. l-8 after having been filledwith liquid and prior to the application of fluid pressure within thesame and when the catheter has a diameter equal to the diameter'of themain portion of the needle lumen;

FIG. 9B is a longitudinal, sectional view corresponding to FIG. 9Aduring the instant when fluid pressure has been applied to the fluidwithin the catheter delivery device of FIG. 9A but prior to the bodilymovement of the catheter from the catheter delivery device;

FIG. 9C is a longitudinal, sectional view corresponding to FIGS. 9A and98 at the moment the catheter within the device has a configurationwhere the flow of fluid is impelling the same from the needle thereof;

FIG. 91) is a longitudinal sectional view of the base portion of theneedle and the enlarged rear end portion of the catheter frictionallylocked within the base of the needle after completion of a catheterejection operation;

FIG. 10A is a greatly enlarged, fragmentary, longitudinal, sectionalview of the front and rear end portions of the catheter containingportions of the catheter delivery device of FIGS. l-8 after having beenfilled with liquid and prior to the application of fluid pressure withinthe same, and when the catheter has a diameter just equal to thediameter of the narrow swaged point of the needle lumen;

FIG. 10B is a longitudinal, sectional view corresponding to FIG. 10Aduring the instant when fluid pressure has been applied to the fluidwithin the catheter delivery device of FIG. 9A but prior to the bodilymovement of the catheter from the needle thereof;

FIG. 10C is a longitudinal, sectional view corresponding to FIGS. 10Aand 108 at the moment the catheter within the device has a configurationwhere the flow of fluid is impelling the same from the catheter deliverydevice;

FIG. 11 is a greatly enlarged view of the front end portion of thecatheter containing portions of the catheter delivery device of FIGS.1-8 after having been filled with liquid and prior to the application offluid pressure within the same, and when the catheter has a diametergreater than that of the main portion of the needle lumen;

FIG. 12 is an enlarged, longitudinal, sectional view of the depressiblebulb-like portion of the catheter delivery devices of FIGS. l-ll afterthe bulb-like portion has been fully compressed to eject the catheterfrom the catheter delivery device;

FIG. 13 is a view showing the separation of the assembly of the end ofthe catheter, infusion liquidreceiving adapter and associated sleevefrom the needle and the attached tubing;

FIG. 14 is a longitudinal, sectional view of the catheter and theinfusion-receiving adapter after the catheter has been fully pulled intointerlocking relationship with the adapter and the adapter attached tothe complimentary connector of an infusion bottle assembly shown in FIG.6;

FIG. 15 is a partially sectional view though a moditied form of catheterdelivery device which includes a unique infusion liquid-receivingadapter construction;

FIG. 16 is a fragmentary longitudinal sectional view through the adapterholding portion of the catheter delivery device of FIG. 15 taken alongsection lines 16-16 therein;

FIG. 17 is a fragmentary, longitudinal, sectional view showing the frontportion of the catheter delivery device in FIG. 15 with the catheterinjected into a blood vessel and the needle withdrawn from the bloodvessel and in the process of being pulled over the catheter and throughthe infusion liquid-receiving adapter;

FIG. 18 is a partly broken away viewv of the remaining portion of theinfusion liquid-receiving adapter and catheter of FIG. 17 afterseparation from the needle, portions of the adapter have been discarded,the catheter has been pulled securely into interlocking relationshipwith the remaining portion of the adapter, and the adapter taped to thepatients body; and

FIG. 19 is a transverse sectional view through the taped remainingportion of the adapter of FIG. 18, taken along section line 19-19thereof.

As shown in FIG. 1, an embodiment of the catheter delivery device of theinvention identified by reference number 1 is shown initially packagedin a sterilized state in a suitable transparent package or container 2in which the device may be sterilized in a conventional way. Thecatheter delivery device 1 as illustrated is designed for injecting acatheter 3 through a cannulated needle 4 or the like into a bloodvessel. However, the

device can be modified for other uses and with or without the use of acannulated needle as a tissue piercing catheter guiding means. Thecatheter delivery device 1 includes a catheter containing body assembly6 comprising a main tubular body portion 6a which may be made of asuitable transparent synthetic plastic tubing. The rear end of thetubing terminates in a laterally extending bulb-like portion 6b, alsomade of a synthetic plastic material, which is the fluid pressureapplying means of the catheter injection device 1. (However, other fluidpressure applying means could be used in the present invention otherthan bulb-like portion.) The cannulated needle 4 is connected to thefront end of the tubing 6a by a hollow needle hub 8 which is somewhatlarger than the tubing 60 and over which hub the tubing is securelyanchored. The needle 4 is anchored within the hub 8. The lumen 4a of theneedle 4 forms a continuation of an open-ended passageway 14 within thetubing 6a. The catheter 3 has an intermediate portion 30 extendingthrough the passageway 14 and a front end portion 3b extending part wayinto the needle 4. Where the length of catheter desired is longer thanthe distance between the bulb-like portion 6b of the catheter containingbody assembly 6 and a point near the forward end of the needle, theintermediate portion 3a of the catheter 3 terminates at the rear thereofin a coiled portion 3c confined in a neatly coiled relation by the wallsof the bulb-like portion 6b.

The bulb-like portion 6b is most advantageously a member having adome-shaped depressible wall 15 (FIG. '12). The tubing 6a has a rear endportion which extends within a tubular extension of the cylindrical wall17 where the tubing communicates with a chamber 22 within the bulb-likeportion 6b. A short compressible tubular section 24 extends rearwardlyfrom the bulb-like portion 6b and has a passageway 18 communicating withthe chamber 22 and forming at the end thereof a portion 180 for snuglyreceiving a connector 23 at the end of an infusion bottle assembly 26(FIG. 6) or other source ofa sterile liquid like saline solution. (Forblood vessel applications, gases like carbon diox ide could be usedinstead of a liquid, but liquids are greatly preferred as the catheterinjection fluid for this application). The tubular section 24 hasfriction fitted in the front end portion of the passageway 18 a plug orpinch valve-forming member 21 which closes the passageway 18. The member21 has a forwardly extending pin-like projection 21a (FIG. 3) over whichthe rear end portion 3d of the catheter most desirably loosely extendsto form a plug or hinderance to fluid flow through the catheter. Thepinching of the tubular section 24 elongates the cross-section thereofas shown in F IG. 7 to form openings on opposite sides of the checkvalve-forming member for passage of fluid into the catheter deliverydevice.

When the dome-shaped wall 15 is depressed, it preferably snaps into aninverted shape as shown in FIG. 12, so that once the bulb is fullycompressed, the depressed wall 15 remains collapsed. However, if thewall 15 is only slightly depressed and released, it returns to itsinitial position. Such slight depression of the wall 15 is sometimescarried out after the needle has been apparently placed in a bloodvessel as an aid in drawing some blood into the catheter delivery devicewhich, if visible through the transparent portions of the device,indicates that the needle tip is located in a blood vessel.

The end of the needle 4 carries a preferably transparent syntheticplastic needle cover 25 best shown in FIG. 8 having an opening 250 atthe front end thereof. The needle cover has fixed therein a longcatheter holding member 27 which extends into the front end portion ofthe needle lumen 4a to prevent movement of the catheter from the needlewhen air is flushed from the device. The catheter holding member 27, asillustrated, has a flat shank portion 27a frictionally held in theneedle cover and terminates in a head portion 2712 outside of the needlecover. The needle cover 25 has a front cylindrical portion 25b defininga corresponding cylindrically shaped passageway 25c therein, thedefining walls of which snugly engage the needle 4. The needle cover 25has a rearwardly outwardly flaring portion 25d which engages around thefront end portion of an infusion liquid-receiving adapter member 29which is used to make connection to the connector 23 of an infusionbottle assembly 26 shown in FIG. 6 after ejection of the catheter fromthe catheter delivery device 1. The flat profile of the shank portion27a of the catheter holding member forms clearance spaces through whichair and liquid can pass through the needle lumen 4a in front of thecatheter and the opening 250 at the front end of the needle cover afterflowing between the catheter and the needle lumen in a manner to bedescribed. The needle cover 25 and the catheter holding member 27carried thereby are removed together as a unit from the needle after airhas been expunged from the catheter delivery device. (Manifestly, theneedle cover 25 and the catheter holding member can have otherconfigurations.)

The base portion of the needle 4 is initially tightly enveloped by thedefining walls of a passageway 46 in the nose portion 30 of the infusionliquid-receiving adapter member 29 made of an expandable resilientplastic material which has a hollow cylindrical rear portion 31 whichfits within the front end of a sleeve 34 preferably made of atransparent synthetic plastic material. The rear end of the sleeve 34has a flanged end portion 35 with an opening 36 into a cylindrical space39 within the sleeve 34. The tubing 60 fits with a slide or loose fitinto the rear sleeve opening 36. The needle hub 8 secured to the frontof the tubing 6a makes a slide frictional fit within the sleeve 34 andcan be removed with the needle 4 from the sleeve by pulling the samerearwardly to separate it from the sleeve, as shown in F 1G.

The catheter 3 is made of a material which is completely inert to bodyfluids and tissue so it can remain indefinitely in the body passageinvolved and does not irritate such tissue. The catheter should also bevery limp and elastic and most desirably when it is to be coiled itshould have a resiliency as well as the limpness of gum rubber or a wellcooked wet noodle. An example of what is meant by a limp and elasticcatheter is one which has an elongation of 450 to 800 percent asdetermined by a STM test procedure P 412. Unlike gum rubber which is notinert to body fluids, a catheter material which has all these qualitiesis silicone elastomer. Limp materials like silicone elastomer remain ina fairly tightly coiled condition idefinitely without any significantcurvature setting therein, so that the catheter will at all times uncoilin a substantially straight condition (i.e. without any significantcurvature). If the catheter has any substantial curvature set therein,it would catch on the walls of the needle or housing, making itimpossible to feed the catheter from the needle. The resiliency of thecatheter material enables the catheter to feed easily from a coiledto astraight configuration and keeps the coils neatly pressed against thewalls of the bulb-like portion 6b.

The catheter 3 preferably has a two-step enlargement at the very rearend thereof, the first enlargement being identified by reference numeral3d and the second enlargement being identified by reference numeral 3d"(FIG. 9A). The pin-like projection 21a of the check valve-forming member21 fits into the interior of the first enlargement 3d preferably looselybut sufficiently close to the catheter walls to reduce the openingtherein to a size where liquid cannot readily enter the same, causing asubstantial pressure drop when fluid tries to flow therethrough. Forexample, a clearance of about 0.002 inch was found to be satisfactory inone case. As shown in FIG. 9A, the outer diameter of the firstenlargement 3d is somewhat greater than the inner diameter of the needlelumen 4a and joins the portion of the catheter in front of the same by aforwardly tapered portion 41 so that when catheter ejection is initiatedand the first enlargement reaches the needle lumen 4a, the tapered partwill become wedged in the needle lumen 4a and reduce the catheterclearance to zero. The wedging of the tapered portion 41 of the firstenlargement 3d of the need] lumen 4a prevents any backward movement ofthe catheter which could bring the catheter against the sharp end of theneedle to sever the catheter. Also, the enlargements 3d and 3d of thecatheter are of such a length and thickness that by pulling on thecatheter 3 the enlargements will distend in length and contract indiameter so the catheter can be readily pulled through the needle 4.

Although the needle hub can have a variety of constructions, as shown,for example, in FIG. 9A, it has a flanged portion 8a from which extendsa reduced forwardly projecting nose portion 8b defining a passageway 8b'into which the cylindrical cannulated needle 4 extends and is anchoredas by swaging the nose portion therearound. This forms a short inwardlyprojecting portion or constriction at 40' within the needle lumen whichdefines an opening or constriction in the needle lumen of less diameterthan the rest of the needle lumen. The needle hub further has arearwardly projecting skirt portion 8c defining an inner cylindricalbore 80 of greater size than said nose portion passageway 8a and mergingtherewith through a tapered opening 8d. The catheter enlargements 3d and3d readily fit within the hub bore 8c. The hub bore 80' communicateswith the rear of the hub 8 through a flared entryway 8c". The outersurface of the skirt is serrated at 45 to form a friction surface overwhich the tubing 6a snugly fits.

As best shown in FIG. 14, when the adapter member 29 is separated fromthe needle 4 after catheter ejection the connector 23 of the infusionbottle assembly 26 shown in FIG. 6 fits into an initially cylindricalopening 40 formed by the rear cylindrical portion 31 thereof. Theadapter member 29 is also provided with a recess 42 behind the noseportion 30 for receiving the second enlargement 3d of the catheter 3after completion of catheter ejection and the removal of the adaptermember and the catheter from the rest of the catheter delivery device ina manner to be explained. The nose portion passageway 46 of the adaptermember after removal from the needle contracts to a size smaller in sizethan the first enlargement 3d at the end of the catheter and into whichsuch enlargement 3d is pulled and seals after catheter ejection.

As previously indicated, the catheter delivery device 1 impels thecatheter 3 by causing a relatively high velocity flow of fluid betweenthe catheter and the defining walls of the needle lumen. This requiresthat at least during the time that the catheter is being ejected fromthe catheter delivery device the catheter 1 must be of a size and shapeto pass freely through the needle lumen 4a. As previously indicated, inaccordance with the invention, catheter ejection is most effectivelyachieved by making the compressible catheter of an initial diameter suchthat it would not freely pass through the needle lumen unless the sizethereof would reduced from its initial size, which is achieved by thecompression of the catheter when fluid pressure is applied thereto. Thecatheter is thus made of a diameter so that it makes initial engagementwith the walls of the needle lumen 4a as, for example, shown in FIG. 9A.

The first step in using the catheter deliverly device 1 is to connectthe catheter delivery device to a source of a sterile liquid like theinfusion bottle assembly 26 shown in FIG. 6, by removing the device fromthe package 2 and connecting the rearwardly projecting tubular section24 of the device to the connector 23 at the end of the infusion bottleassembly 26. The catheter delivery device is then picked up and held sothat the tip of the needle points upwardly, and a pinch clamp 46 of theinfusion bottle assembly is released to permit infu sion liquid to passto the connector 23. The compressible tubular section 24 of the catheterdelivery device is then squeezed to permit the infusion fluid to flowinto the device until liquid flows through the opening 25a at the end ofthe needle cover 25 indicating that the air above the same has beenexpunged from the device. The tubular section 24 is then released anddisconnected from the infusion connector 23. During the fillingoperation, the liquid readily rises within the catheter delivery deviceand first fills the bulb-like portion 6b and pushes any air upwardlyahead of the same. The fluid also enters the rear or bottom end of thecatheter because it is only loosely obstructed by the pin-likeprojection 21a, to flush air from the catheter. When the air and theliquid reaches the bottom portion of the needle lumen 4a, although thecatheter engages the walls of the needle lumen, the compressible natureof the catheter and the lower pressure within the catheter resultingfrom the drop in fluid pressure as the liquid flows through theobstructed rear end of the catheter and the length of the catheterbehind the point where the catheter enters the needle lumen enables thepressure caused by the pressure head of the infusion bottle systemslightly to compress the catheter so the air and liquid can pass aroundthe catheter and gain access to the clearance spaces between the shankportion 27a of the catheter holding member 27 and the upper or front endof the needle lumen and between the shank portion 27a of the catheterholding member 27 and the needle cover 25, ultimately passing throughthe opening 25a in the end of the needle cover.

When the catheter delivery device is ready to be used for catheterinjection, the needle cover 25 and the catheter holding member 27carried thereby are removed by pulling the same from the end of theneedle 4. The needle 4 is then inserted into the blood vessel involvedand after a tourniquet has been applied in the usual manner for needleinsertion, the depresssible wall 15 of the bulb-like portion 6b is fullydepressed to inject the catheter 3 into the blood vessel involved.

In FIGS. 9A through 93, the catheter 3 is shown as having a diameterequal to the diameter of the needle lumen 4a (and therefore somewhatgreater than the diameter of the constricted portion of the needle lumenat 4a). For example, the constriction at 4a may be 0.003 inch less thanthe diameter of the rest of the needle lumen. FIG. 9A illustrates thecondition of the catheter delivery device 1 before application ofpressure thereto. When the catheter 3 is lubricated with alcohol or thelike, it has been found that when its diameter is equal to the diameterof the needle lumen the catheter can be manually slid by the lumenconstriction at 4a" into the position shown in FIG. A. When thebulb-like portion 6b of the catheter delivery device is depressed, thissudden application of appreciable pressure initially causes acompression of the portion of the catheter positioned rearwardly of theneedle lumen 4b as shown in FIG. 98. While this pressure is notinstantaneously applied to the radially outwardly facing surfaces of theportion of the catheter within the needle lumen, which surfaces contactthe needle lumen walls, the juncture between the compressed portion ofthe catheter within the tubing 6 a and the portion of the catheterwithin the needle lumen not yet compressed is a gradually outwardlyflaring portion 50. This outwardly flaring portion exposes a smallexterior portion of the catheter at the base of the needle lumen towhich the fluid pressure is applied and this portion of the catheter isfully compressed to form another outwardly flaring portion immediatelyin front of the same. It can thus be seen that, upon initial applicationof fluid pressure, the portion of the catheter within the needle lumenbecomes progres sively compressed until the entire length thereof leavescontact with the needle lumen walls. Then the flow of fluid isinstrumental in effecting movement of the catheter from the needlelumen, and when the catheter reaches the outer end of the needle lumen,as shown in FIG. 9C, the catheter sharply expands to the diameter of theneedle lumen. The pressure conditions against the catheter vary somewhatalong the length of the needle lumen from a point where it leaves theneedle lumen where the pressure is a minimum and equal to the patientsblood pressure to a point deeply within the lumen where a maximumpressure is realized. There will, therefore, be a slightly progressiveoutward flaring of the catheter for its full length within the needlelumen even after it completely leaves contact with the needle lumen, andthis outwardly flaring portion of the catheter as well as the moresharply outwardly expanding portion of the catheter as it leaves theneedle lumen provides rearwardly facing surfaces against which liquidpressure is applied to form a piston-like action which cooperates withthe force applied to the catheter by the friction of fluid flowtherearound, to impart a greater impelling force to the catheter.

Some liquid also flows into and along the inside of the catheter as aresult of the depression of the bulb-like portion 6a, but the frictionto such flow in the long and initially obstructed catheter causes asubstantial pres sure drop in the catheter aiding in the cathetercompression described. The resulting high velocity flow of liquid aroundthe catheter causes such a sudden movement of the catheter that thecatheter movement occurs faster than the flow of liquid in the catheterand little or no liquid actually flows out of the catheter duringcatheter ejection. When the enlarged rear end of the catheter reachesthe base of the needle lumen 4a, the tapered part 41 of the firstenlargement 3d of the catheter wedges in the needle lumen walls. Therather large momentum of the catheter does not pull the rear end of thecatheter through the needle lumen because when the enlargement reachesand enters the needle lumen, there is suddenly only liquid flow in thecatheter (which has left the pin-like extension 21a) which causes aresultant outward expansion of the catheter within the needle lumen,firmly to lock the catheter in place within the needle lumen.

The present invention also includes the use of a catheter whose outerdiameter is approximately equal to or slightly greater than the diameterof the constricted portion of the needle lumen at 4a and somewhatsmaller than the remaining diameter of the needle lumen. Thisapplication of the invention is illustrated in FIGS. 10A, 10B and 10Cwhich respectively show the condition of the catheter before applicationof fluid pressure, at the instant of initial application of fluidpressure and when the fluid pressure and resultant fluid flow has causedthe catheter to leave the needle lumen. As shown in FIG. 10B, theinitial compression of the catheter instantaneously causes the catheterto lose contact with the constriction of the needle lumen and therebyprovides a piston-like profile which is instantaneously instrumental ineffecting movement of the catheter from the lumen as it provides ashoulder against which the fluid pressure propels the catheter forwardlyalong with the friction of the moving fluid against the sides of thecatheter.

The present invention is also effective when the catheter is of agreater size than the diameter of the needle lumen for its full length,such as an oversize of 0.005 inch. In this embodiment of the inventionshown in FIG. 11, it is not readily possible to mount the catheterwithin the needle lumen prior to the application of pressure to thecatheter. Accordingly, the front end of a preferably modified catheter 3having preferably a beveled tip 53 in the needle hub bore 80' wherethere is preferably only the tapered surface 8d in front of theoversized catheter against which the catheter can strike. Uponapplication of fluid pressure by depression of the bulb-like portion 6b,the catheter is guided into the needle lumen adjacent to which it islocated and is compressed by the pressure conditions involved for thesame reasons and in the same manner as shown in FIGS. 9A-9C.

After catheter injection, the needle is withdrawn from the patient, theuser grasps the flanged portion 35 of the sleeve 34 with one hand(usually the left hand) and pulls on the tubing 6a with the other handto bring the needle hub 8 against a small shoulder 55 (FIG. 12) at therear of the sleeve 34 where the tip of the needle is retracted withinthe infusion liquid-receiving adapter member 29. The assembly of theadapter member 29, the sleeve and the catheter are held together as aunit by pinching the portion of the sleeve 34 around the adapter 29 withone hand which compresses the desirably compressible adapter around thecatheter to hold the same in place while the tubing is pulled sharplywith the other hand. This stretches and elongates the catheterenlargement 3d and 3d'fland the rest of the catheter to reduce the sizethereof where it slips from the needle lumen. The sleeve 34 now actslike a catheter holding skirt by preventing the catheter from droppingupon contaminating surfaces. The catheter is then pulled fully into theadapter member 29 where it is drawn into its extreme position therein,as shown in FIG. 14. The sleeve 34 is pulled from the adapter member 29and thrown away. The rear cylindrical portion 31 of the adapter member29 may then be connected to the connector 23 of the infusion bottleassembly 26.

Refer now to FIGS. 15-19 which illustrates a modification of the presentinvention involving, among other things, the elimination of the sleeve34 which is primarily for the purpose of protecting the catheter whenthe catheter is pulled into position within the adapter member 29, andthe inclusion of a modified infusion liquidreceiving adapter assembly29. Also, the catheter 3" utilized is much longer than the catheters 3previously described in that it is not necessary to use an obstructionlike the plug-forming extension 21a in the open rear end of the catheterto reduce the pressure at the point where the catheter engages theneedle lumen walls to an extent permitting the escape of air and fluidaround the catheter under relatively small pressure head conditions.(The catheter 3" is, of course, fully impelled into the blood vesselinvolved and after catheter ejection would be withdrawn from the bloodvessel an amount to leave the desired length of catheter in the bloodvessel.)

One of the reasons for the modified adapter assembly 29 in addition tosimplifying the construction of the device by eliminating the sleeve 34,is that it permits a tighter fit between it and the enlarged rear end ofthe catheter 3". It should be noted that the adapter assembly 29' aswell as the adapter member 29 previously described are preferablyinitially slidably mounted around the exterior of the needle 4. In orderto permit the expandable adapter member 29 in the previously describedembodiments of the invention to be pulled along the needle without toomuch difficulty, the smallest interior passage thereof cannot be verymuch smaller than the needle diameter so the adapter member is notstretched too tightly over the needle lumen. Accordingly, when thecatheter 3 is pulled into sealing position within the base of theadapter member 29, it

-is sometimes possible to so distend the enlarged end of the catheter(whose maximum size is limited) to a point where it can be pulledcompletely through the not very much smaller passageway of the adaptermember in which it is to be locked and sealed. This is not possible withthe adapter assembly 29' now to be described.

As best shown in FIG. 15, the modified catheter delivery device,although having a much longer catheter 3", is of the same overall lengthas the previously described catheter delivery device 1, the additionalspace for the longer catheter being obtained by providing many moreadditional coils in the portion of the catheter within the bulb-likeportion 6b. Also, the enlarged rear end of the catheter 3" is locatedcompletely within the bulb-like portion 6b.

As best shown in FIG. 16, the adapter assembly 29 includes a main bodymember 58 which ultimately forms a liquid-passing connector attachableto the said infusion bottle system connector 23 or other connectors. Themain body member which is preferably made of a relatively rigid moldedsynthetic plastic material has a main central tubular portion 58a havinga straight passageway extending from the inlet to the outlet endthereof. This passageway has a relatively small front passageway portion60a at the front end of the main body member 58 which loosely receivesthe needle.

The front passageway portion 60a joins a relatively large passagewayportion 62, the front end of which is defined by an abutment shoulder 64formed by a transversely extending wall 66. An annular groove 68 isformed in the larger passageway portion 62.

There is located at the forward end of the larger passageway portion 62of the main body member 58 a resilient rubber-like seat-forming sleeve70 which is expanded to fit over the needle 4. The seat-forming sleevehas a passageway 70 extending therethrough, the defining walls of whichin the contracted condition of the sleeve form a slide friction fit withthe catheter 3" and a very tight fit with the first enlargement 3d atthe end of the catheter 3". The seat-forming sleeve 70 may be held inplace against the aforementioned shoulder 64 by a cylindrical holdingmember 72 which fits within the rear end of the large passageway portion62 of the main body member 58. The holding member '72 is releasablyinterlocked within the main body member 58 and projects from the rearend thereof where it can be grasped after removal of the adapterassembly 29 from the needle to separate it from the main body member 58.To this end, the holding member 72 may include an annular rib 72a on theoutside thereof which releasably snaps into the aforementioned annulargroove 68 in the large passageway portion 62 of the main body member 58.The holding member 72, which is also preferably made of a relativelyrigid synthetic plastic material, has an open ended passageway 72b whichloosely fits on the needle 4.

The adapter assembly 29 is frictionally held on the base of the needleby the seat-forming sleeve 70 which frictionally engages the needle 4.However, the friction between the confronting surfaces of the sleeve 70and the needle 4 is such that a modest longitudinal force applied to theentire adapter assembly 29' can pull the assembly off of the needle 4. Aneedle cover 25' with a catheter holding member (not shown) is removablysecured around the front end of the main body member 58.

The most advantageous means for effecting movement of the adapterassembly 29 off of the needle 4 is a flexible elongated pull tab 75,which may be made of any suitable material which can withstand thetensile strength required to pull the adapter assembly 29' from theneedle 4 and also to overcome the small force which opposes the pullingof the catheter 3" from the needle lumen. The pull tab 75 has an opening77 at the inner end thereof which loosely fits around the holding member72. This inner end portion of the pull tab is held in place against therear end of the holding member 72 by radial projections 80 of the mainbody part 58. The pull tab 75 has a relatively large front end portion75a having an opening 79 therein.

The pull tab 75 has a length so it can extend substantially beyond thefront end of the needle 4. The degree to which the pull tab 75 extendsbeyond the needle is important for reasons to be explained.

The main body member 58 of the adapter assembly 29' is provided withdiametrically opposed radial projections 80-80 which are adapted tointerlock with one form of liquid-passing connector (not shown)different from the infusion bottle system connector 23 to whichconnector the main body member 58 may be secured subsequent to itsseparation from the rest of the catheter delivery device. As willappear, only the main body member 58 is ultimately used to makeconnection to an external source of liquid like an infusion bottleassembly. The holding member 72 is ultimately disconnected from the mainbody member 58 to permit the insertion within the rear end of the largerpassageway portion 62 of liquid-passing connector like connector 23 ofthe infusion bottle system 26.

After catheter ejection is effected, the removal of the adapter assembly29' and the catheter 3" from the needie 4 is effected by first placingthe enlarged front end portion 75a of the pull tab 75 against theportion of the ejected catheter immediately beyond the front end of theneedle 4, as indicated by the dashed line position thereof shown in FIG.17. The catheter 3" is gripped tightly through the opening 79 of theenlarged front end portion of the pull tab which then has substantialslack therein so the pull tab and the catheter can be pulled a distancetogether from the end of the needle without effecting any movement ofthe adapter assembly. In the example of the invention illustrated in thedrawings (see especially FIG. 17), when the pull tab while gripping thecatheter therethrough has been pulled to its fullest extent so anyfurther movement of the pull tab will effect sliding movement of theadapter assembly on the needle, the catheter has been distended to apoint where the second enlargement 3d" thereof begins sliding along theneedle lumen. 1n the illustrated embodiment of the invention where therear end of the catheter 3" is initially spaced behind the adapterassembly 29' (although contiguous thereto), the distention of thecatheter without movement of the adapter assembly in effect brings thefinal position of the rear end of the catheter closer to the inlet endof the adapter assembly 29'. Thus, when the catheter leaves the needlelumen and the tension in the catheter is relieved, the rear end of thecatheter will snap into a position within the interior of the adapterassembly where it cannot touch any contaminating surfaces. (However, thebroadest aspect of the invention envisions a catheter snapping into aposition outside of but yet adjacent to the end of the adapterassembly.) The degree of slack provided in the pull tab when it isplaced against the catheter just beyond the front end of the needle is,therefore, selected to provide just this result.

When the portion of the main body member 58 of the adapter assemblycontaining the seat-forming sleeve 70 leaves the needle, the sleeve 70contracts snugly around the catheter 3 thereby to fix the relativeposition between the adapter assembly 29 and the rear end of thecatheter 3". After both the catheter 3" and the adapter assembly 29'have been pulled from the end of the needle, the catheter is grasped andpulled as far as it can be pulled within the adapter assembly whichbrings the first enlargement 3d of the catheter within the passageway 70of the seat-forming sleeve 70. The distance which the rear end of thecatheter has to move upon leaving the needle lumen to snap into the endof the adapter is minimized in the illustrated embodiment of theinvention by the fact that the adapter assembly is positioned adjacentthe needle hub 8 at a point preferably spaced only a small distanceforwardly of the point where the enlarged rear end portion of thecatheter becomes wedged in the needle lumen after catheter ejection. Thepulling of the enlargement 3d within the sleeve 70 expands the sleevetightly against the defining walls of the large passageway section 62 ofthe main body member 58 to form such a firm and tight seal andconnection between the catheter and the sleeve at this point that it isimpossible to pull the catheter through this sleeve. The holding member72 is then pulled from the body member 58 and discarded with the pulltab.

The tubular portion 58a of the main body member 58 of the adapterassembly. has a completely flat surface 82 on one side thereof in aplane extending longitudinally thereof. The main body member has a pairof outwardly projecting wings 8484 which on one side thereof arecoplanar with and form an extension of the flat surface 82. The wings8484 give the main body member 58 lateral stability when placed againstthe skin 85 of the users body adjacent the point where the catheter 3enters the same as shown in FIG. 19. The main body member 58 when viewedin transverse cross ection as shown in FIG. 19, has a generallytriangular or tapered configuration providing thin, marginal,longitudinal sides so a string of adhesive tape 86 can securely retainthe main body member 58 by engaging the skin immediately beyond the thinlongitudinal sides 82a82a of the flat surface 82.

It is apparent that the embodiments of the present invention describedabove provides an exceedingly effective, easy to use, and relativelyinexpensive means for injecting catheters into blood vessels andseparating the catheters from the same and securing the catheters to aliquid-passing connector. The same principles of the invention utilizedin the injection of catheters by liquid into blood vessels can beapplied in readily injecting compressible catheters or other slimelongated members into other passageways of the body with liquid or air.While elongated members made of silicone elastomer (which isincompressible in solid form) must be hollow or have other spaces formedtherein like catheters to be compressible, the invention could be usedto inject other elongated members in solid form which are readilycompressible in such form.

It should be understood that numerous modifications may be made in themost preferred forms of the invention described without deviating fromthe broader aspects of the invention.

1 claim:

1. In a medical device for injecting an elongated member into apassageway of the body of an animal or human, the device including ahousing having a feeding nose portion with means for emplacing thefeeding nose portion in said passageway and from which feeding noseportion said elongated member is to be ejected into said passagewayafter the feeding nose portion has been inserted therein, said feedingnose portion having an open-ended lumen communicating with afluidholding space within said housing, said housing to contain fluid tobe pressurized and including means for effecting the pressurizing ofsaid fluid so as to cause a flow of fluid through said lumen and aroundan elongated member therein with sufficient velocity to impel theelongated member therethrough, the improvement comprising: an elongatedmember contained within said housing space, said elongated member havinglimp and elastic consistency and extending into or in close proximity tosaid lumen of said feeding nose portion, said elongated member having anoutside diameter at least about the size of the minimum diameter of thelumen of said feeding nose portion so as not to be freely passablethrough the lumen when the elongated member is in its initial state,said elongated member being sufficiently compressible that under saidfluid pressurization the elongated member compresses to a size less thansaid minimum diameter of said lumen where fluid is forced by saidpressure around the elongated member in said lumen to eject the sametherefrom, and means for preventing the ejection of the rear end portionof the elongated member from said feeding nose portion lumen.

2. The medical device of claim 1 wherein the portion of the elongatedmember to be ejected from the lumen is at least about the size ofsubstantially all portions of the lumen of said feeding nose portion.

3. The medical device of claim 1 wherein the lumen of said feeding noseportion has a construction therein and the portion of the elongatedmember to be ejected from the lumen is at least about the size of saidconstruction but smaller than the size of the rest of the lumen.

4. The medical device of claim 1 wherein the portion of the elongatedmember to be ejected from the lumen is initially slightly larger thansubstantially all portions of the lumen of said feeding nose portion.

5. The medical device of claim 1 wherein said pressure effecting meansis a manually movable means which is a part of said medical device, saidelongated member being so compressible that a modest application offorce applied to said movable means is sufficient to create the pressurein said housing which compresses the elongated member to a size lessthan said minimum diameter of the feeding nose portion lumen.

6. The medical injection device of claim 2 wherein said pressureeffecting means is a manually movable means incorporated in said medicaldevice, said elongated member being so compressible that a modestapplication of force applied to said movable means is sufficient tocreate said pressure in said housing which compresses the elongatedmember to a size less than said minimum diameter of the feeding noseportion lumen.

7. The medical device of claim 1 wherein said elongated member is acatheter having a passageway extending therethrough.

8. The medical device of claim 7 wherein said fluid is a sterile liquidbut said housing is initially free of such liquid, there is providedconnector means for filling said housing with said sterile liquid from asource of such liquid which may have only a few feet of head pressure,the rear end of said catheter is permanently completely open, and saidcatheter having such a length such that the resistance to liquid flowthrough said passageway thereof reduces the pressure therein at thepoints where the catheter engages the walls of said feeding nose portionlumen, so that filling said housing with said liquid at said headpressure provides sufficient pressure around the catheter at said pointsthat the catheter will compress so said liquid and air ahead of the samepass around the catheter.

9. The medical device of claim 7 wherein said fluid is a sterile liquidbut said housing is initially free of such liquid, there is providedconnector means for filling said housing with said sterile liquid from asource of such liquid which may have only a few feet of head pressure,said catheter is of insufficient length that liquid flow through thesame under said head pressure will cause a sufficient pressure drop atthe points where the catheter engages the walls of said feeding noseportion lumen to enable said head pressure to compress the catheter topermit flow of air and fluid flow around the catheter, and there isprovided catheter closure means for obstructing the open rear end ofsaid catheter to produce said pressure drop at said points where thecatheter engages the walls of the feeding nose portion lumen.

10. The medical injection device of claim 9 wherein said feeding noseportion is a cannulated needle, said means for preventing the ejectionof the rear end of said catheter including an enlargement on the endthereof which is not compressible by said fluid pressurization to thedegree to pass through said lumen of said needle under the fluidpressure and which becomes frictionally locked in the needle lumen whenit reaches the same, the fluid pressure in the catheter then expandingthe catheter outwardly to lock the same in the lumen, and said catheterclosure means temporarily initially obstructs said rear open end of saidcatheter so that the ejection of said catheter through said feeding noseportion lumen separates the rear end of the catheter from said catheterclosure means.

11. The medical device of claim 10 wherein said catheter closure meansincludes a portion projecting loosely within the rear end of thecatheter.

12. The medical device of claim 11 wherein said device is provided witha compressible tubular extension having a passageway for makingconnection between an external source of liquid to constitute said fluidin said device and the interior of said housing, there being aplug-forming member snugly fitted within said passageway to close thesame off from the exterior of the device, said tubular extension whenpinched between the users fingers elongates in a given direction toseparate the same from said plug-forming member at the points ofelongation thereof to form clearance spaces for the passage of saidliquid into said housing, and said portion projecting into said rear endof the catheter being a forwardly projecting extension on saidplugforming member.

13. The medical device of claim 4 wherein the front end of the elongatedmember is initially positioned immediately contiguous to the inlet endof the lumen of said feeding nose portion.

14. The medical device of claim 13 wherein the front end of saidelongated member is tapered readily to be guided into said feeding noseportion lumen.

15. In a medical device for feeding a catheter into a blood vessel orother passageway, the device comprising a housing defining a catheterholding space and including a feeding nose portion through which thecatheter is to be guided into said passageway, a catheter in said space,the catheter being made of a resilient readily manually stretchablematerial and having an enlarged portion at the rear end portion thereofwhich blocks the complete passage thereof from said space so the rearend portion of the catheter cannot be ejected from the device, saidenlarged portion at the rear end of the catheter being such that bymanually pulling on the portion of the catheter projecting from thefeeding nose portion the enlarged portion will distend to a point wherethe catheter slips from said space through said feeding nose portion,and a liquid-passing adapter means adapted to fit a complimentaryliquid-passing connector communicating with a liquid-holding container,said adapter means having an open-ended passageway the defining walls ofwhich are initially in spaced surrounding relation to said catheter butslidably frictionally fits around said feeding nose portion, saidadapter means and catheter, on the one hand, and at least said feedingnose portion of said housing on the other hand, being manually separableafter the catheter has been injected into said passageway by pulling thesame relatively apart, said adapter means passageway having at least oneportion within which the enlarged rear end portion of the cathetersealingly fits, the improvement comprising: pull tab means attached tosaid adapter means and extendable to a point beyond the end of saidfeeding nose portion where the pull tab means and an ejected portion ofthe catheter can be held together with one hand while a part of saidhousing is grasped with the other hand, so that by pulling one hand awayfrom the other the adapter means and catheter can be separated from thefeeding nose portion.

16. The medical device of claim wherein said pull tab means is aflexible elongated member extendable to a point substantially beyond theend of said feeding nose portion, the initial inlet end of said adaptermeans is positioned forwardly of said enlargement on said catheter whenthe enlargement is in said locked portion in said housing, said flexibleelongated pull tab member being adapted initially to be positionedagainst a portion of the ejected catheter at the end of the feeding noseportion where there is slack in the pull tab member and when pulledoutwardly with the catheter from this point until the pull tab is tautthe catheter is distended and pulled without movement of said adaptermeans, the slack in said pull tab member when initially positioned atthe end of said feeding nose portion is such that when the catheter andadapter means are finally separated from the feeding nose portion bycontinuation of the pulling of said pull tab member and catheter, thecatheter is at least in the vicinity of said adapter means where itquickly contracts into a position adjacent to or inside of said adaptermeans passageway to avoiding striking contaminated surface.

17. The medical device of claim 16 when said slack in said pull tabmember is equal to the distance the catheter must be distended tofinally release the rear end of the catheter for movement in saidhousing.

18. The medical device of claim 15 wherein the initial normal positionof said adapter means and the enlarged portion of said catheter in saidblocked position is such that upon pulling said pull tab member andcatheter to the point where both are separated from said feeding noseportion, the rear end of the catheter is located inside of said adaptermeans passageway.

19. The medical device of claim 15 wherein said enlarged portion on theend of said catheter is of a size to become frictionally locked withinsaid feeding nose portion upon catheter ejection, and said adapter meansis slidably and frictionally mounted around said feeding nose portion.

20. The medical device of claim 15 wherein said adapter means isinitially mounted around said feeding nose portion and includes a mainbody portion made of a relatively rigid material which body portionincludes a passageway which loosely surrounds the feeding nose portion,a resilient expandable sleeve anchored in the latter passageway andexpanded into frictional engagement around said feeding nose portion,and the enlarged portion of said catheter being pullable into sealingrelation with said sleeve when said catheter and adapter means arepulled from said feeding nose portion, the sleeve being expanded by saidenlarged portion of the catheter against the defining walls of saidadapter means passageway.

21. The medical device of claim 15 wherein said pull tab means has anopening at the inner end thereof which receives and surrounds saidfeeding nose portion at a point rearwardly of said adapter means, saidhousing having a portion projecting outwardly thereof behind said innerend of said pull tab means, said pull tab means being confined betweenthe rear end of said adapter means and said enlarged portion of saidhousing, a forward pull on said pull tab means bringing the inner end ofthe pull tab means against the rear end of said adapter means to movethe same forwardly along said feeding nose portion.

22. The medical device of claim 20 wherein said expandable sleeve insaid adapter means passageway is anchored to said passageway by aholding member removably anchored within the rear end of said adaptermeans passageway which holding member includes an open ended passagewaythe defining walls of which initially loosely fit around said feedingnose portion and upon removal of the adapter means from the feeding noseportion receives and surrounds a portion of the catheter ejected fromthe device, said holding member being removable from said main bodyportion of the adapter means to free the rear end portion of saidadapter means passageway to receive said complimentary liquid-passingconnector.

23. The medical device of claim 15 wherein said adapter means has a mainbody portion with a relatively fiat side adapted to lay against the skinwhere the main body portion can be immobilized thereagainst by a stripof adhesive tape applied thereover.

24. The medical device of claim 23 wherein said main body portion hasoutwardly extending portions providing substantial surface areas bothlongitudinally and transversely of the main body portion to stabilizethe same when resting against a skin surface.

25. The medical device of claim 23 wherein said main body portion hasouter surfaces meeting the longitudinal side margins of said fiatsurface at an acute angle thereby forming relatively thin longitudinaledges so adhesive tape enveloping the same makes contact with the skinadjacent the point where it makes contact with the main body portion ofthe adapter means.

26. In a device for feeding a catheter through a feeding nose into ablood vessel or other passageway, the device including a body from whichthe feeding nose extends, the body and feeding nose defining a space, acatheter in said space to be fed through the feeding nose into thepassageway involved, the catheter being made of a resilient readilymanually stretchable material and having an enlarged portion at the rearend portion thereof which prevents the passage thereof from said spaceso the rear end portion of the catheter cannot be ejected from thedevice, said enlarged portion at the rear end of the catheter being sucha size that, by manually pulling on the portion of the catheterprojecting from the feeding nose, the enlarged portion will distend to apoint where the catheter slips from said space through said feedingnose, the improvement comprising a liquid-passing adapter means adaptedto fit a complimentary liquid-passing connector communicating with aliquid-holding container, said liquidpassing adapter means including amain body portion made of a relatively rigid material and including apassageway the defining walls of which loosely surround said feedingnose, a resilient expandable seat-forming sleeve anchored in saidpassageway and frictionally engaging around said feeding nose, saidadapter means and catheter, on the one hand, and at least said feedingnose, on the other hand, being manually separable after the catheter hasbeen injected into said passageway, and said enlarged portion of saidcatheter being pullasaid passageway, said holding member being made of arelatively rigid material and having an open ended passageway which isinitially loosely received around the feeding nose and which when theadapter means is removed from the feeding nose, is removable from therear end of said passageway of said main body portion of the adaptermeans to provide clearance for the insertion of said complimentaryliquid-passing connector.

1. In a medical device for injecting an elongated member into apassageway of the body of an animal or human, the device including ahousing having a feeding nose portion with means for emplacing thefeeding nose portion in said passageway and from which feeding noseportion said elongated member is to be ejected into said passagewayafter the feeding nose portion has been inserted therein, said feedingnose portion having an open-ended lumen communicating with afluid-holding space within said housing, said housing to contain fluidto be pressurized and including means for effecting the pressurizing ofsaid fluid so as to cause a flow of fluid through said lumen and aroundan elongated member therein with sufficient velocity to impel theelongated member therethrough, the improvement comprising: an elongatedmember contained within said housing space, said elongated member havinglimp and elastic consistency and extending into or in close proximity tosaid lumen of said feeding nose portion, said elongated member having anoutside diameter at least about the size of the minimum diameter of thelumen of said feeding nose portion so as not to be freely passablethrough the lumen when the elongated member is in its initial state,said elongated member being sufficiently compressible that under saidfluid pressurization the elongated member compresses to a size less thansaid minimum diameter of said lumen where fluid is forced by saidpressure around the elongated member in said lumen to eject the sametherefrom, and means for preventing the ejection of the rear end portionof the elongated member from said feeding nose portion lumen.
 2. Themedical device of claim 1 wherein the portion of the elongated member tobe ejected from the lumen is at least about the size of substantiallyall portions of the lumen of said feeding nose portion.
 3. The medicaldevice of claim 1 wherein the lumen of said feeding nose portion has aconstruction therein and the portion of the elongated member to beejected from the lumen is at least about the size of said constructionbut smaller than the size of the rest of the lumen.
 4. The medicaldevice of claim 1 wherein the portion of the elongated member to beejected from the lumen is initially slightly larger than substantiallyall portions of the lumen of said feeding nose portion.
 5. The medicaldevice of claim 1 wherein said pressure effecting means is a manuallymovable means which is a part of said medical device, said elongatedmember being so compressible that a modest application of force appliedto said movable means is sufficient to create the pressure in saidhousing which compresses the elongated member to a size less than saidminimum diameter of the feeding nose portion lumen.
 6. The medicalinjection device of claim 2 wherein said pressure effecting means is amanually movable means incorporated in said medical device, saidelongated member being so compressible that a modest application offorce applied to said movable means is sufficient to create saidpressure In said housing which compresses the elongated member to a sizeless than said minimum diameter of the feeding nose portion lumen. 7.The medical device of claim 1 wherein said elongated member is acatheter having a passageway extending therethrough.
 8. The medicaldevice of claim 7 wherein said fluid is a sterile liquid but saidhousing is initially free of such liquid, there is provided connectormeans for filling said housing with said sterile liquid from a source ofsuch liquid which may have only a few feet of head pressure, the rearend of said catheter is permanently completely open, and said catheterhaving such a length such that the resistance to liquid flow throughsaid passageway thereof reduces the pressure therein at the points wherethe catheter engages the walls of said feeding nose portion lumen, sothat filling said housing with said liquid at said head pressureprovides sufficient pressure around the catheter at said points that thecatheter will compress so said liquid and air ahead of the same passaround the catheter.
 9. The medical device of claim 7 wherein said fluidis a sterile liquid but said housing is initially free of such liquid,there is provided connector means for filling said housing with saidsterile liquid from a source of such liquid which may have only a fewfeet of head pressure, said catheter is of insufficient length thatliquid flow through the same under said head pressure will cause asufficient pressure drop at the points where the catheter engages thewalls of said feeding nose portion lumen to enable said head pressure tocompress the catheter to permit flow of air and fluid flow around thecatheter, and there is provided catheter closure means for obstructingthe open rear end of said catheter to produce said pressure drop at saidpoints where the catheter engages the walls of the feeding nose portionlumen.
 10. The medical injection device of claim 9 wherein said feedingnose portion is a cannulated needle, said means for preventing theejection of the rear end of said catheter including an enlargement onthe end thereof which is not compressible by said fluid pressurizationto the degree to pass through said lumen of said needle under the fluidpressure and which becomes frictionally locked in the needle lumen whenit reaches the same, the fluid pressure in the catheter then expandingthe catheter outwardly to lock the same in the lumen, and said catheterclosure means temporarily initially obstructs said rear open end of saidcatheter so that the ejection of said catheter through said feeding noseportion lumen separates the rear end of the catheter from said catheterclosure means.
 11. The medical device of claim 10 wherein said catheterclosure means includes a portion projecting loosely within the rear endof the catheter.
 12. The medical device of claim 11 wherein said deviceis provided with a compressible tubular extension having a passagewayfor making connection between an external source of liquid to constitutesaid fluid in said device and the interior of said housing, there beinga plug-forming member snugly fitted within said passageway to close thesame off from the exterior of the device, said tubular extension whenpinched between the user''s fingers elongates in a given direction toseparate the same from said plug-forming member at the points ofelongation thereof to form clearance spaces for the passage of saidliquid into said housing, and said portion projecting into said rear endof the catheter being a forwardly projecting extension on saidplug-forming member.
 13. The medical device of claim 4 wherein the frontend of the elongated member is initially positioned immediatelycontiguous to the inlet end of the lumen of said feeding nose portion.14. The medical device of claim 13 wherein the front end of saidelongated member is tapered readily to be guided into said feeding noseportion lumen.
 15. In a medical device for feeding a catheter into ablood vessel Or other passageway, the device comprising a housingdefining a catheter holding space and including a feeding nose portionthrough which the catheter is to be guided into said passageway, acatheter in said space, the catheter being made of a resilient readilymanually stretchable material and having an enlarged portion at the rearend portion thereof which blocks the complete passage thereof from saidspace so the rear end portion of the catheter cannot be ejected from thedevice, said enlarged portion at the rear end of the catheter being suchthat by manually pulling on the portion of the catheter projecting fromthe feeding nose portion the enlarged portion will distend to a pointwhere the catheter slips from said space through said feeding noseportion, and a liquid-passing adapter means adapted to fit acomplimentary liquid-passing connector communicating with aliquid-holding container, said adapter means having an open-endedpassageway the defining walls of which are initially in spacedsurrounding relation to said catheter but slidably frictionally fitsaround said feeding nose portion, said adapter means and catheter, onthe one hand, and at least said feeding nose portion of said housing onthe other hand, being manually separable after the catheter has beeninjected into said passageway by pulling the same relatively apart, saidadapter means passageway having at least one portion within which theenlarged rear end portion of the catheter sealingly fits, theimprovement comprising: pull tab means attached to said adapter meansand extendable to a point beyond the end of said feeding nose portionwhere the pull tab means and an ejected portion of the catheter can beheld together with one hand while a part of said housing is grasped withthe other hand, so that by pulling one hand away from the other theadapter means and catheter can be separated from the feeding noseportion.
 16. The medical device of claim 15 wherein said pull tab meansis a flexible elongated member extendable to a point substantiallybeyond the end of said feeding nose portion, the initial inlet end ofsaid adapter means is positioned forwardly of said enlargement on saidcatheter when the enlargement is in said locked portion in said housing,said flexible elongated pull tab member being adapted initially to bepositioned against a portion of the ejected catheter at the end of thefeeding nose portion where there is slack in the pull tab member andwhen pulled outwardly with the catheter from this point until the pulltab is taut the catheter is distended and pulled without movement ofsaid adapter means, the slack in said pull tab member when initiallypositioned at the end of said feeding nose portion is such that when thecatheter and adapter means are finally separated from the feeding noseportion by continuation of the pulling of said pull tab member andcatheter, the catheter is at least in the vicinity of said adapter meanswhere it quickly contracts into a position adjacent to or inside of saidadapter means passageway to avoiding striking contaminated surface. 17.The medical device of claim 16 when said slack in said pull tab memberis equal to the distance the catheter must be distended to finallyrelease the rear end of the catheter for movement in said housing. 18.The medical device of claim 15 wherein the initial normal position ofsaid adapter means and the enlarged portion of said catheter in saidblocked position is such that upon pulling said pull tab member andcatheter to the point where both are separated from said feeding noseportion, the rear end of the catheter is located inside of said adaptermeans passageway.
 19. The medical device of claim 15 wherein saidenlarged portion on the end of said catheter is of a size to becomefrictionally locked within said feeding nose portion upon catheterejection, and said adapter means is slidably and frictionally mountedaround said feeding nose portion.
 20. The medical device of claim 15wherein said Adapter means is initially mounted around said feeding noseportion and includes a main body portion made of a relatively rigidmaterial which body portion includes a passageway which looselysurrounds the feeding nose portion, a resilient expandable sleeveanchored in the latter passageway and expanded into frictionalengagement around said feeding nose portion, and the enlarged portion ofsaid catheter being pullable into sealing relation with said sleeve whensaid catheter and adapter means are pulled from said feeding noseportion, the sleeve being expanded by said enlarged portion of thecatheter against the defining walls of said adapter means passageway.21. The medical device of claim 15 wherein said pull tab means has anopening at the inner end thereof which receives and surrounds saidfeeding nose portion at a point rearwardly of said adapter means, saidhousing having a portion projecting outwardly thereof behind said innerend of said pull tab means, said pull tab means being confined betweenthe rear end of said adapter means and said enlarged portion of saidhousing, a forward pull on said pull tab means bringing the inner end ofthe pull tab means against the rear end of said adapter means to movethe same forwardly along said feeding nose portion.
 22. The medicaldevice of claim 20 wherein said expandable sleeve in said adapter meanspassageway is anchored to said passageway by a holding member removablyanchored within the rear end of said adapter means passageway whichholding member includes an open ended passageway the defining walls ofwhich initially loosely fit around said feeding nose portion and uponremoval of the adapter means from the feeding nose portion receives andsurrounds a portion of the catheter ejected from the device, saidholding member being removable from said main body portion of theadapter means to free the rear end portion of said adapter meanspassageway to receive said complimentary liquid-passing connector. 23.The medical device of claim 15 wherein said adapter means has a mainbody portion with a relatively flat side adapted to lay against the skinwhere the main body portion can be immobilized thereagainst by a stripof adhesive tape applied thereover.
 24. The medical device of claim 23wherein said main body portion has outwardly extending portionsproviding substantial surface areas both longitudinally and transverselyof the main body portion to stabilize the same when resting against askin surface.
 25. The medical device of claim 23 wherein said main bodyportion has outer surfaces meeting the longitudinal side margins of saidflat surface at an acute angle thereby forming relatively thinlongitudinal edges so adhesive tape enveloping the same makes contactwith the skin adjacent the point where it makes contact with the mainbody portion of the adapter means.
 26. In a device for feeding acatheter through a feeding nose into a blood vessel or other passageway,the device including a body from which the feeding nose extends, thebody and feeding nose defining a space, a catheter in said space to befed through the feeding nose into the passageway involved, the catheterbeing made of a resilient readily manually stretchable material andhaving an enlarged portion at the rear end portion thereof whichprevents the passage thereof from said space so the rear end portion ofthe catheter cannot be ejected from the device, said enlarged portion atthe rear end of the catheter being such a size that, by manually pullingon the portion of the catheter projecting from the feeding nose, theenlarged portion will distend to a point where the catheter slips fromsaid space through said feeding nose, the improvement comprising aliquid-passing adapter means adapted to fit a complimentaryliquid-passing connector communicating with a liquid-holding container,said liquid-passing adapter means including a main body portion made ofa relatively rigid material and including a passageway the definingwalls of which looSely surround said feeding nose, a resilientexpandable seat-forming sleeve anchored in said passageway andfrictionally engaging around said feeding nose, said adapter means andcatheter, on the one hand, and at least said feeding nose, on the otherhand, being manually separable after the catheter has been injected intosaid passageway, and said enlarged portion of said catheter beingpullable into sealing relation with the interior of said sleeve whensaid catheter and adapter means are pulled from said feeding nose, thesleeve being sized to be expanded by the presence therein of theenlarged portion of said catheter against the defining walls of saidadapter means passageway.
 27. The device of claim 26 wherein saidseat-forming sleeve is anchored within said passageway of said main bodyportion of the adapter means by a holding member removably anchoredwithin the rear end portion of said passageway, said holding memberbeing made of a relatively rigid material and having an open endedpassageway which is initially loosely received around the feeding noseand which when the adapter means is removed from the feeding nose, isremovable from the rear end of said passageway of said main body portionof the adapter means to provide clearance for the insertion of saidcomplimentary liquid-passing connector.